JP2015526875A - Meandering flow field with varying number of channel parts - Google Patents

Abstract

An exemplary flow field comprises a plurality of flow channel portions. There are n inlet portions configured to introduce fluid into the flow field. A plurality of first path portions guide fluid flow in the first direction. A plurality of second path portions guide fluid flow in a second direction that is substantially parallel to and opposite to the first direction. A plurality of third path portions guide fluid flow in the first direction. The n outlet portions are configured to discharge fluid from the flow field. n is an integer, and the number of portions in at least one of the plurality of path portions is a non-integer multiple of n.

Description

  The subject matter of this disclosure generally relates to components comprising a flow field. More particularly, the subject matter of this disclosure relates to flow field configuration.

  This invention was made with government support under Contract No. CA-04-7003-00, signed with the US Department of Transportation. Accordingly, the US Government has certain rights in this invention.

  Fuel cells are useful for generating electricity. A fuel cell facilitates an electrochemical reaction between reactants such as hydrogen and oxygen. The reactant or coolant distribution plate comprises a flow field having a plurality of channels that direct the reactant or coolant within the battery stack assembly. Various flow field configurations have been proposed. For example, a serpentine flow field comprises portions of adjacent flow channels that direct reactant or coolant fluids in opposite directions. One of the features of the serpentine flow field configurations is that they allow humidification of areas that may be drier along the flow path. One of the challenges associated with realizing a serpentine flow field for a fluid distribution plate is that the space on the plate is limited, especially when the desired number of flow paths increases, a special design issue. It is to be considered.

  An exemplary flow field comprises a plurality of flow channel portions. There are n inlet portions configured to introduce fluid into the flow field. A plurality of first path portions guide fluid flow in the first direction. A plurality of second path portions guide fluid flow in a second direction that is substantially parallel to and opposite to the first direction. A plurality of third path portions guide fluid flow in the first direction. The n outlet portions are configured to discharge fluid from the flow field. n is an integer, and the number of portions in at least one of the plurality of route portions is a non-integer multiple of n.

  Various features and advantages of the disclosed exemplary embodiments will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows.

1 schematically illustrates an exemplary fuel cell component designed in accordance with an embodiment of the present invention. FIG. FIG. 6 schematically illustrates another exemplary embodiment. FIG. 6 schematically illustrates another exemplary embodiment. FIG. 6 schematically illustrates another exemplary embodiment. The figure which shows schematically the characteristic of symmetry of either of the Example of FIGS.

  The flow field of the disclosed embodiment has several n inlet and outlet portions. The flow field comprises a non-integer multiple of channel portions between the inlet and outlet portions. The disclosed flow field configuration is quite useful in a variety of situations. Fuel cells require a flow field that distributes fluids such as reactants and coolants. Other devices, such as flow batteries, include a flow field, and the disclosed embodiments can be useful with such devices. The fuel cell components with flow fields are discussed for discussion purposes in the following description.

  FIG. 1 schematically illustrates a fuel cell component 20. In this example, the fuel cell component 20 is a reactant distribution plate.

  The flow field 22 includes a plurality of channels that direct fluid within the fuel cell. In the illustrated embodiment, the flow field 22 is configured to direct fluid flow within the fuel cell. This embodiment is useful for directing coolant flow to humidify and dissipate heat within the fuel cell.

  The example flow field 22 includes a plurality of inlet portions 24. This embodiment comprises five inlet portions 24. The inlet portion 24 is configured to introduce a fluid, such as a coolant, into the flow field 22 in a direction toward the plurality of first path portions 26 (eg, upward according to the drawing).

  The illustrated embodiment includes eight first path portions 26 that connect to the inlet portion 24 for fluid flow from the inlet portion 24 into the first path portion 26. Is done. The first path portion 26 is disposed in the flow field 22 to direct fluid flow in a first direction along a portion of the plate 20. In the drawing, the first direction is substantially horizontal and from left to right. The first direction of fluid flow is intended to direct fluid toward the plurality of second path portions 28.

  In the illustrated embodiment, there are nine second path portions 28 connected to the first path portion 26 for fluid movement from the first path portion 26 into the second path portion 28. The second path portion 28 guides fluid flow along another portion of the plate 20 in a second direction that is generally parallel to and opposite the first direction. The second path portion 28 directs fluid flow toward the third path portion 30 along the second direction.

  The illustrated embodiment includes eight third path portions 30, which are second for fluid flow from the second path portion 28 into the third path portion 30. Connected to the path portion 28. The third path portion 30 directs fluid flow in a third direction that is the same as the first direction in the illustrated embodiment (eg, from left to right in the drawing). The third path portion 30 directs fluid flow toward the outlet portion 32.

  The illustrated embodiment comprises five outlet portions 32. The outlet portion 32 is configured to drain fluid from the flow field 22.

  As can be seen from the drawing, the flow field 22 flows into the inlet section 24, along the first path section 26, along the second path section 28, then along the third path section 30, and finally at the outlet. It has a general flow of fluid moving along portion 32.

  In the illustrated embodiment, there are an equal number of inlet portions 24 and outlet portions 32. The number of route portions in at least one route portion of the plurality of route portions is a non-integer multiple of the number of entrance portions. That is, when there are n inlet portions and outlet portions, at least one of the plurality of route portions includes a number of portions that is a non-integer multiple of n. In the embodiment of FIG. 1, there are 2n-2 first path portions and 2n-2 third path portions. In the embodiment of FIG. 1, there are 2n-1 second path portions. By providing a different number of path portions and utilizing a non-integer multiple of the number of inlet and outlet portions, the limited available on fuel cell components such as reactant or coolant distribution plates A larger number of inlet and outlet portions can be accommodated in the space.

  Different numbers can have various numbers of path portions. If there are n inlet portions and n outlet portions, 2n−a first path portions, 2n−b second path portions, and 2n−c third path portions are Exists. In the embodiment of FIG. 1, a and c are equal. In the embodiment of FIG. 1, a and c are equal to 2 and b is equal to 1. In view of this description, those skilled in the art will realize other possible values for a, b or c that will fit the needs of their particular situation.

  Considering the different number of path parts and the incorporation of non-integer multiples of path parts, there are splits along at least some of the flow paths of the flow field 22, and at least some of the flow paths There is a fusion part along. In the embodiment of FIG. 1, the flow path starting at the inlet portion 24-2 comprises a split at 40, so that the inlet portion 24-2 extends from the inlet portion 24-2 to the first path portion 26. -2 and 26-3 are connected to each of the first path portions 26-2 and 26-3 for fluid movement to each of them. In the embodiment of FIG. 1, there is a similar split where the inlet portion 24-3 is connected to each of the first path portions 26-4, 26-5. Similar splits exist along the flow path starting at the inlet portion 24-4 where the inlet portion 24-4 is connected in fluid communication with each of the first path portions 26-6, 26-7. To do.

  In the embodiment of FIG. 1, the flow path starting at the inlet portion 24-1 does not include a split. The flow path starting at the inlet portion 24-5 is such that the first path portion 26-8 allows fluid flow into the second path portions 28-8, 28-9. At a location connected to each of −8, 28-9, a split is provided at 42 near the end of the first path portion 26-8.

  The embodiment of FIG. 1 includes a fusion portion at 44 where each of the second path portions 28-1, 28-2 is connected in fluid communication with the third path portion 30-1. . Where each of the third path portions 30-6, 30-7 is connected to the outlet portion 32-4 to allow fluid flow into the outlet portion 32-4, another fusion portion is formed at 46. Indicated. In the embodiment of FIG. 1, as can be seen from the drawing, the outlet portions 32-1, 32-5 are each connected in fluid communication with a single path portion of the third path portion.

  In the embodiment of FIG. 1, each flow path of the flow field 22 comprises at least one split or at least one fusion. Most of the flow path is provided with a split part and a fusion part. Splits and fusions facilitate the use of different numbers of path portions and non-integer multiples of the number n of inlet portions 24. By using a number of path portions that are a non-integer multiple of the number n of the inlet portions 24, a wider number of inlet portions 24 can be used, while fuel cell components such as fluid distribution plates It is still possible to realize a meandering flow field in the limited area available above. The flow field of the reactant and coolant distribution plates generally requires a consistent channel pitch, and for any desired number of inlet sections, an integer multiple of that number is the size of the fuel cell component. It cannot be adapted to a meandering configuration within the constraints of Accommodates a larger number of inlet sections that feed into multiple path sections establishing a serpentine flow field configuration, with the illustrated embodiment including a varying number of path sections and the use of a non-integer multiple number of coefficients can do.

  FIG. 2 shows another exemplary embodiment. In this embodiment, the number of inlet portions 24, outlet portions 32, first path portions 26, second path portions 28, and third path portions 30 are each equal to the number included in the first embodiment. . One difference between the embodiment of FIGS. 1 and 2 is that the splitting portion 42 of the embodiment of FIG. 1 is not included in the embodiment of FIG. Instead, a split at 50 is included where the first path portion 26-1 is connected in fluid communication with each of the second path portions 28-1, 28-2. Instead of the fusion portion 44 of the embodiment of FIG. 1, the embodiment of FIG. 2 is connected such that each of the first path portions 28-8, 28-9 are in fluid communication with the third path portion 30-8. Where 52 is provided with a fusion section. In other respects, the embodiment of FIG. 2 includes many of the features of FIG.

  FIG. 3 shows another exemplary embodiment. In this embodiment, the at least one flow path does not comprise a split or a fusion part. The flow path comprising the inlet portion 24-3, the first path portion 26-4, the second path portion 28-5, the third path portion 30-5, and the outlet portion 32-3 can be any other It is a direct and uninterrupted flow path that does not split or fuse with the flow path part. The configuration of the splitting part 50 and the fusion part 52 in the embodiment of FIG. 3 is the same as that of the embodiment of FIG. The split near the end of the other inlet portion (except for the inlet portion 24-3) is similar to that of FIG.

  FIG. 4 schematically shows the configuration of another embodiment. This embodiment also comprises at least one flow path that does not comprise a split or a fusion part. The flow path established by the inlet portion 24-3, the first path portion 26-5, the second path portion 28-5, the third path portion 30-4, and the outlet portion 32-3 is Along with it, there are no splits or fusions. In this sense, the embodiment of FIG. 4 is the same as the embodiment of FIG. The structure of the division | segmentation part and fusion | melting part in the Example of FIG. 4 is different compared with another Example. The split portions at 42 and 44 are included in the embodiment of FIG. 4 as are the split portions 42 and 44 of the embodiment of FIG. The embodiment of FIG. 4 includes a split 60 where the inlet portion 24-1 is connected in fluid communication with the first path portions 26-1, 26-2. The fusion portion 62 establishes a fluid communication connection between the third path portions 30-7 and 30-8 with the outlet portion 32-5.

  Each of the embodiments of FIGS. 1-4 has rotational symmetry. FIG. 5 schematically shows reference lines 70, 72 that intersect at the center of the component 20. Each flow field configuration of the embodiment of FIGS. 1-4 is symmetric about an axis along the intersection of reference lines 70, 72 when rotated 180 °. Realizing rotational symmetry facilitates manufacturing savings.

  The majority of the splitting portion of the channel in the illustrated embodiment is at the connection between the inlet portion and the two first path portions. Most of the fusion part is at the connection between the two third path parts 30 and the outlet part 32. For each flow path comprising a split at the connection between the inlet part and the first path part, complementary with a fusion at the connection between the corresponding third path part and the outlet part By providing split and fused portions so that there is a flow path, rotational symmetry is maintained and flow imbalance distribution is minimized. As the flow field is rotated 180 °, each flow path exchanges position and configuration with a complementary flow path. There can be one flow path complementary to itself. Further, for each inlet portion 24 that splits into two first path portions 26, complementary and in fluid communication with two third path portions 30 that are fused and complementary to the two first path portions 26. There is a simple exit portion 32. In either case, the flow path does not include a plurality of split sections or a plurality of fusion sections.

  In the embodiment of FIGS. 1 and 2, the internal splits and fusions include a flow path that is reconnected to a flow path that is different from the flow path at which the flow path splits. In these embodiments, one of the inlet portions 24 does not include a split portion and one of the outlet portions 32 does not include a fusion portion. In the embodiment of FIGS. 1 and 2, each flow path comprises at least one split or at least one fusion. In the embodiment of FIGS. 3 and 4, as described above, there is at least one flow path with no splits or fusions.

  The above description is exemplary rather than limiting in nature. Changes and modifications to the disclosed embodiments that do not necessarily depart from the essence of the invention will be apparent to those skilled in the art. The scope of legal protection given to this invention can only be determined by studying the following claims.

Claims (16)

A flow field comprising a plurality of flow channel portions, wherein the plurality of flow channel portions are
N inlet portions configured to introduce fluid into the flow field;
A plurality of first path portions for directing fluid flow in a first direction;
A plurality of second path portions that direct fluid flow in a second direction that is substantially parallel to and opposite to the first direction;
A plurality of third path portions for directing fluid flow in a first direction;
N outlet portions configured to drain fluid from the flow field;
Wherein n is an integer and the number of path portions in at least one path portion of the plurality of path portions is a non-integer multiple of n.   Fluid flow along the flow field travels through the inlet portion toward the first path portion, travels through the first path portion toward the second path portion, and passes through the second path portion. The flow field of claim 1, wherein the flow field travels through the third path portion and through the third path portion toward the exit portion. The number of path portions in at least one path portion of the plurality of path portions is 2n−y;
The flow field of claim 1, wherein y is a non-zero integer.   4. A flow field according to claim 3, wherein y is equal to 1 or 2.   The flow field of claim 1, wherein the number of path portions in each of the plurality of path portions is a non-integer multiple of n. There are 2n−a first path parts,
There are 2n−b second path portions,
6. A flow field according to claim 5, wherein there are 2n-c third path portions.   The flow field of claim 6, wherein a is equal to c but not equal to b. a is 2,
c is 2,
8. A flow field according to claim 7, wherein b is 1. Each of the at least some inlet portions is connected in fluid communication with the plurality of first path portions;
Each of the at least some outlet portions is in fluid communication with the plurality of third path portions;
At least one inlet portion is connected in fluid communication with only one first path portion;
The flow field of claim 1, wherein the at least one outlet portion is connected in fluid communication with only one third path portion.   The at least one flow field channel is one inlet portion and is connected in fluid communication with only one first path portion that is connected in fluid communication only with the one inlet portion. An inlet portion, a second path portion connected in fluid communication with only this one first path portion, and a 1 connected in fluid communication with only this one second path portion The flow field of claim 9, comprising: a third path portion and an outlet portion.   The flow field of claim 1, wherein the flow field comprises a reactant or coolant distribution plate and the flow field channel is established on at least one side of the distribution plate.   12. A flow field according to claim 11, wherein the flow field is rotationally symmetric on the plate such that the flow field has the same configuration with respect to a reference at the center of the plate. The flow field is a plurality of flow paths, each flow path having at least one inlet portion, at least one first path portion, at least one second path portion, and at least one third path. Comprising a plurality of flow paths comprising a path portion and at least one outlet portion;
At least some of the flow paths comprise a split portion of one portion, into split portions into adjacent upstream portions connected in fluid communication with the one portion;
The at least some flow paths comprise a fusion portion of two parts, the fusion part to an adjacent upstream part connected in fluid communication with the two parts. The described flow field.   14. A flow field according to claim 13, wherein at least one flow path does not comprise a split.   14. A flow field according to claim 13, wherein at least one flow path does not comprise a fusion part.   14. A flow field according to claim 13, wherein at least one flow path does not comprise a split section and does not comprise a fusion section.

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